mtd: gpmi: add on-flash BBT support for gpmi nand

add the on flash bbt support for gpmi nand driver.
Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Documentation/devicetree/bindings/mtd/gpmi-nand.txt

@@ -12,6 +12,10 @@ Required properties:
   - interrupt-names : The interrupt names "gpmi-dma", "bch";
   - fsl,gpmi-dma-channel : Should contain the dma channel it uses.
 
+Optional properties:
+  - nand-on-flash-bbt: boolean to enable on flash bbt option if not
+                       present false
+
 The device tree may optionally contain sub-nodes describing partitions of the
 address space. See partition.txt for more detail.
 

drivers/mtd/nand/gpmi-nand/gpmi-nand.c

@@ -27,6 +27,7 @@
 #include <linux/pinctrl/consumer.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_mtd.h>
 #include "gpmi-nand.h"
 
 /* add our owner bbt descriptor */
@@ -1502,6 +1503,8 @@ static int __devinit gpmi_nfc_init(struct gpmi_nand_data *this)
 	chip->ecc.size		= 1;
 	chip->ecc.strength	= 8;
 	chip->ecc.layout	= &gpmi_hw_ecclayout;
+	if (of_get_nand_on_flash_bbt(this->dev->of_node))
+		chip->bbt_options |= NAND_BBT_USE_FLASH | NAND_BBT_NO_OOB;
 
 	/* Allocate a temporary DMA buffer for reading ID in the nand_scan() */
 	this->bch_geometry.payload_size = 1024;